class Student(object):
    def __init__(self, name, score):
        self.name = name
        self.score = score

    def get_grade(self):
        if self.score >= 90:
            return "A"
        elif self.score >=60:
            return "B"
        else:
            return "C"

lisa = Student("Lisa", 99)
bart = Student("Bart", 59)
print(lisa.name, lisa.get_grade())
print(bart.name, bart.get_grade())